Production cost, hydrogen

In case methanol is used as an intermediate fuel (e.g. in mobile fuel cells), the cost of methanol production is of interest. Produced from fossil fuels, notably natural gas, at a price of 3 US GJ, reforming or series reactor schemes lead to a methanol production cost estimated around 5.5 US GJ (Lange, 1997). Advanced micro-structured string-reactors for this concept are under development (Homy et ah, 2004). 

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Considering the prospective hydrogen production cost, the main conclusion is that these still have to be decreased to compete with fossil fuel-based technology, and improved performance in this respect can be obtained by... 

The economics and C02 emissions of the different hydrogen production technologies are summarised in Figs. 10.10 and 10.11, which illustrate the major differences of specific hydrogen-production costs for different technologies and feedstocks. 

Section 14.4.2 (but excluding C02 prices for fossil fuels, unlike in the MOREHyS model) the dotted lines for the CCS cases indicate the additional costs for C02 transport and storage. Increases in feedstock prices could significantly increase hydrogen-production costs, owing to their high shares of total costs for some... 

Table 17.3. Hydrogen production costs from different feedstocks in EU25 neighbouring countries in 2040 (prices in 2005)...

Hydrogen production costs depend, to a very large extent, on the assumed feedstock prices. The typical range until 2030 is between 8 and 12 ct/kWh ( 2.6- 4/kg). In the long term, until 2050, with an expected increase in feedstock prices (fossil fuels) and C02 prices, hydrogen production costs will increase as well. 

An economic analysis of hydrogen production costs indicates that in comparison with hydrogen produced in USA, hydrogen generation in Niyazoba will be much cheaper, particularly if the electricity is supplied at zero cost to the electrolizer plant. In this case, the usage of hydrogen as a fuel in automobiles will be significantly increased because of its low cost and environmental friendly nature. 

In order to assess the actual potential of the sulphur-iodine cycle for massive hydrogen production at a competitive cost, CEA has been conducting an important programme on this cycle, ranging from thermodynamic measurements to hydrogen production cost evaluation, with flow sheet optimisation, component sizing and investment cost estimation as intermediate steps. The paper will present the method used, the status of both efficiency and production cost estimations, and discuss perspectives for improvement. 

The sulphur-iodine cycle was demonstrated in Japan (Kubo, 2004), so there is little doubt it can indeed continuously produce hydrogen. The question of its feasibility therefore only arises when related to industrially acceptable conditions, both from the point of view of the efficiency and of the hydrogen production cost. It is to address this question that the US DOE and French CEA teamed up to build an Integrated Laboratory Scale experiment (Russ, 2009), with prototypical operating conditions that could be extrapolated to a large scale production plant. 

Hydrogen production cost Plant capital cost... 

Transforming the efficiency and the investment cost into the resulting hydrogen production cost requires a techno-economic model. CEA uses an economic model based on a levelised approach hydrogen selling price is set to equalise revenues and expenses over the plant life. In other terms, all expenses are split over the whole production of the plant, with the use of a discount rate to take into account the different years at which expenses and production take place. 

Figure 4 Decomposition of hydrogen production cost for a Nth of a kind plant...

With all these assumptions, the hydrogen production cost from the sulphur-iodine cycle is estimated to be slightly less than EUR 10 kgH2. This value is much higher than the estimated hydrogen production cost from alkaline electrolysis at the same production scale, about EUR 3 to 4 kgH2 for comparable energy unit costs. 

CEA has conducted a wide-ranging assessment of the sulphur-iodine cycle for massive hydrogen production. In particular, the hydrogen production cost was estimated, and found to be higher than what was anticipated. Although uncertainties do remain and areas for process improvements have been identified, the sulphur-iodine cycle competitiveness appears to require breakthroughs in efficiency increase and investment cost reduction. 

Table 2 Results of H2A cost analysis for hydrogen production costs using the Cu-CI cycle...

H2A analysis was used to predict hydrogen production costs as shown in Table 2. These results are based on the use of solar power tower as the heat source and also include assumptions that have yet to be validated. Work is ongoing in these areas. Nevertheless, the preliminary hydrogen production costs as well as the preliminary efficiency numbers indicate that the Cu-CI cycle has promise and that further R D is justifiable. 

A preliminary evaluation of the hydrogen production costs based on solar, nuclear and hybrid operation lead to the following results Small plants are powered most favourably by solar energy, while nuclear plants are most economic at high power levels > 300 MW(th) hybrid systems may have their niche in the mid-range of 100 to 300 MW(th). 

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